Conventionally, some image forming apparatuses such as multi-functional peripherals have a function of displaying a preview of image data that is the object of the output to be printed or sent.
Japanese Laid-Open Patent Publication No. 2005-73015 discloses a technique which determines whether image data displayed for previewing is a character image or a gradation image, and when it is a character image, displays the image by setting a preview magnification as to be enough to recognize the characters.
In addition, in recent years, an image forming apparatus that is a machine for copying only (that is, a copier) is getting multi-functions including a color copy, fax, filing, and a mail, and the function becomes more complicated. The more complicated the function becomes, the more possible that an operational error occurs. When the operational error is allowed, printing or sending is actually performed with the error, sheets are wasted and a security problem occurs. Of course, such an error may occur in a mono-functional copier and the like.
Such an operational error described above occurs because a user is not skilled in a method for using the image forming apparatus. Accordingly, in order to prevent the operational error, conventionally, as many as possible explanations have been described in an operational screen with a limited display area or otherwise training of the method for using has been performed for the user. In any method, to cause the user to get used in an actual apparatus, the operational error is allowed, printing sheets are wasted, and trouble that data with no security problem is sent may occur.
On the other hand, conventionally, image forming apparatus have been provided with various function limits. Examples thereof include, (1) as a result of authentication, except for a registered user, use is not permitted, (2) an upper-limit of the number of copies or the like is set individually for each user, and the use beyond the limit is not permitted, (3) a use limit of a function, fax is not usable, for example, is set individually for each user.
These function limits and use limits are effective for excluding a user, however, it is not possible to cause a user who is not familiar to the method of using the apparatus to study and get used thereto.
In addition, there is a preview function as described in Japanese Laid-Open Patent Publication No. 2005-73015, however, when a preview display is performed for all image data that is an object of an output irrespective of level of skill of a user, it is troublesome for a skilled user, and on the other hand, when a preview display is not performed for all image data, there is more possibility that an unskilled user as described above outputs image data with an operational error remained.